Method for making repairs



p 3, 1940. H. w. HARMAN 2,198,167

METHOD FOR MAKING REPAIRS Original Filed Aug. 7, 1937 III!!! Enventor 4 170] W Farman/ Patented Apr. 23, 1940 UNITED STATES PATENT OFFICE Original application August 7, 1937, Serial No.

157,972, now Patent No. 2,142,896, dated January 3, 1939.

Divided and this application January 10, 1938, Serial No. 184,315

Claims.

The present invention relates to improvements in methods for making repairs and is a division of my co-pending application entitled Fastenings and methods for producing the same filed Au- 5 gust 7, 1937, Serial No. 157,972 issued on Jan. 3,

1939, as Patent No. 2,142,896.

An object of the invention is to provide an improved method for joining the two separated parts of a piece of metal across a crack, including the steps and'processes of the method by which an effective locking of the two parts of the metal is secured without the use of heat.

Another object of the invention resides in certain improved steps and processes of a cold method for the application of locking fastenings to two parts of metal to be joined together in which such steps and processes are few, simple and economical, being designed to be carried out in a very short space of time.

50 An important object of the invention is to increase the tensile strength of the metal parts I to a very high degree due to the tensile strength of the locking fastenings which are applied and spread by a cold method to the joint.

35 The invention also contemplates the use of certain improved tools for expeditiously carrying out the steps and processes of the improved method.

With the foregoing and other objects in view, the invention will be more fully described here- 30 inafter, and will be more particularly pointed out in the claims appended hereto.

In the drawing, wherein like symbols refer to like or corresponding parts throughout the several views.

35 Figure 1 is a fragmentary perspective view of two pieces of metal initially drilled for receiving the improved locking fastenlngs.

Figure 2 is a similar view showing a subsequent step in the method in which the fastening is completed.

Figure 3 is a sectional view taken through two pieces of metal with the locking fastenings applied therein in drill holes made completely through the pieces.

5 Figure 4 is a similar view in which the drill holes do not pass completely through the metal pieces.

Figure 5 is a perspective view of the improved locking fastening.

Figure 6 is a longitudinal section taken on the line 66 in Figure 5.

Figure 7 is a perspective view of one form of drilling template employed.

I Figure 8 is a. plan view of the drilling template a asapplied to the work.

Figure 9 is a side elevation of an improved punch shown in place for flattening the improved locking fastenings.

Figure 10 is a cross-section taken on the line Ill-40 in Figure 9, and

Figure 11 is a side view, partly broken away, showing the implement for holding the drilling template in fixed position.

Referring more particularly to the drawing, and for the present to Figures 5 and 6, l2 desig- 1o nates generally one of the improved locking fastenings which is made up of appropriate metal of desired gauge or thickness, and includes a number of bulged or enlarged locking parts separated by diminished connecting necks. In the 15 instance illustrated, three such bulged or enlarged parts l3, l4 and I5 are employed, being connected with one another by the reduced necks l6 and l I. The locking fastenings are cup-shaped, as shown in Figure 6 having the flanges I 8 extending at substantially right angles to the general plane of the bulged or enlarged portions. The bulged or enlarged portions may be of the concavo convex form shown in Figure 6 for a double purpose; first, to add stability to the fastening as a unit independent of the repair in which it is used; and secondly to give lateral spread or extension to the fastenings when hammered down. In other words these fastenings are commercial units which are punched or stamped out of flat metal to the form shown in Figures 5 and 6 and theymust posses a suificient rigidity to maintain their commercial form until applied to the repair. Both the flange l8 and the concavo-convex construction of the enlarged or bulged portions will tend to impart this stability. The cupped form of the fastening increases its dimensions when it is flattened to enable it to fit tightly into the lock design as hereinafter explained.

The most desirable metal for making these locking fastenings is a metal or alloy of metals that has a high ductility, possesses strength, and has the quality of becoming stronger and harder when worked cold. Such characteristics or properties are found principally in the alloys of nickel iron, nickel steel, chromium nickel iron and chromium nickel steel. These alloys possess a tensile strength of from to thousand pounds per square inch when annealed. When hammer drawn cold, the tensile strength can be increased 50 on some of these alloys to as high as 300 thousand pounds per square inch. Also, the hardness may be increased from to 460 Brinell hardness test.

In Figure 1 is shown two pieces or two parts of metal l9 and 20 to be Joined together, or l9 and 20 55 may represent two separated parts of a cylinder block or the like in which has developed a crack 2 l As shown in Figure 1 the metal parts 18 and 20 are drilled in accordance with a machined design which corresponds generally with the con. figuration of the unitary locking fastening i2. As many of these machined designs may be drilled into the metal parts 19 and 20 across the crack 21 as deemed desirable. In Figure 1 three such machined designs are produced. Two of these designs 22 and 23 extend cross-wise of the crack 21 and act in a locking capacity to hold the two pieces [Band 20 of the metal together and from moving apart. The intermediate design 24 is disposed lengthwise of the crack 21 and acts in a sealing capacity.

These machined designs may be produced in any appropriate manner, preferably according to the following procedure:

A center hold 25 is first drilled in the casting preferably centrally through the crack 2|. This hole 25 may be drilled all the way through the metal pieces 19 and 20, as shown in Figures 1 and 3, or it may be drilled only partially through 25 the casting as shown in Figure 4 leaving shelves 26 of the metal pieces l9 and 20 lying beneath the drilled-out parts. These shelves 26 act as abutments or backings for ,the operatiom of punching the fastenings in place. Where the hole is drilled all the way through the metal parts as shown in Figure 3 the casting will have to be laid on an anvil, the anvil giving the necessary backing or abutment.

Into this hole 25 so drilled'is inserted the shank 21 of the drilling template 28 shown more particularly in Figures 7 and 8. The drilling template has guide holes 29 and 30 therein; one hole 29 being to one side of the shank 21, and the other hole 30 being to the diametrically opposite side of 49 the shank 21. Using these guide holes 29 and 30 as guides for the drill, while the shank 21 occupies the center casting hole 25, two additional holes 3| and 32 are drilled in the casting pieces I9 and 20. Due to the fact that the shank 21 has 5 cut away rounded portions 33 at opposite sides thereof into which the drill occupying the guide holes 29 and 30 is received, the casting holes 31 and 32 will overlap, and communicate with, the center initially-produced casting hole 25. There 50 will be thus produced in the casting or in the metal parts 19 and 23 a machineddesigncomposed of the holes 25, 3| and 32, which machined design will conform to the design of the fastening unit shown in Figures 5 and 6.

55 As shown in Figures 7 and 8 one upper edge of the template 28 may be flattened as indicated at 34. In this flattened part 34 is a socket 35 for the reduced nose 36 of an instrument 31, shown in Figures 8 and 11 for the purpose of holding the go template 28 against rotation. The socket 35 may be produced in the template without the use of the flattened portion 34, if desired. It will be seen from Figure 7 that the shank 21 projects both above and below the template 28, so that the 65 template may be applied from either side to the central opening 25. This is an advantage in enabling quick and easy application of, the template, and in avoiding the annoyance of having to select one side of the template before the same 70 will fit the repair. It will be further noted that the shank 21 is longer at one side of the template than at the other to accommodate varying thicknesses of castings or metal pieces 19, 20. As indicated in dotted lines in Figure 8, the underside u of the template may be formed with a flattened edge 38 and with a socket 39 for use when the template is reversed; that is for readily receiving the nose 36 of instrument 31. This instrument 31, broken away in Figure 8, may extend out any desired length to exert appropriate leverage upon the template 28 in rotating the same with the shank 21 in the hole 25, thereby bringing the'lateral guide holes 29 and 30 into relatively proper positions with respect to the transverse line across the crack 21. ables the operator to hold the drilling template 28 firmly against movement during the drilling of the holes 31 and 32. After the second hole 32 is drilled, the instrument 31 may be inserted through the guide hole 30 in the template and 15 into the hole 32, thus locking the drilling template 28 against any casual rotation during the drilling of the third hole 31.

After the drilling of the three holes 25, 32 and 3|, the drilling template is removed, and the bot- 20 toms of all three holes are squared with a flat nose drill; that is where the construction shown in Figure 4 is employed.

After drilling the first design, the second design 24 may be drilled longitudinally of the crack 2| 25 and prior or'subsequent thereto, the other locking design 23 may be drilled across the crack 2!. As many of the designs both cross-wise and longitudinally of crack 21 may be drilled as found necessary. 30 After the designs are drilled, the same are filled by inserting one locking fastening of the type shown in Figures 5 and 6 into the design and flattening out such metal fastenings so that it fits the machined design tightly. .35 The method of accomplishing this step is shown in'Figure 9 in which a punch 40 is shown having three prongs 41, 42 and 43 combining together to form a design conforming to that of the machined design in the casting. The flat- 4o tening of the metal fastenings accomplished by one or more sharp hammer blows delivered upon the punch 40, the prongs of which rest upon one of the locking fastenings as shown in Figure 9. After one fastening is flattened another one 45 is inserted above it and the punch action follows. As many fastenings are inserted in the machined design as necessary to fill the same. Each fastening is flattened by subsequent operation of the punch 40.

The fastenings in the designs 22 and 23 extend across the crack 21 and act to tightly lock the metal parts 19 and 20 at opposite sides of the crack 2|, preventing it from opening or expanding at the crack, and at the same time imparting to the repair part tensile strength of the fastening at its smallest part. By employing a metal of high tensile strength in the making of the fastenings, more tensile strength may be imparted to the repair. By knowing the tensile strength of the metal of the fastenings and by calculating the square of the fastening at its smallest part, the tensile strength of the repair may be calculated with mathematical exactness.

This is impossible to do with any other type of repair or weld.

The repair is extremely elastic and strong, yet it does not leave any strain in the parts as it tightly locks the parts 13 and 20 together in the precise relation to their original parts. Therefore, there are no strains created on the part of the process, as is the case when castings are welded.

The invention may be used for a number of purposes, for instance the repairing of cracked 15 The instrument 31 also en- 0 or broken castings, such as motor cylinder blocks and heads, Diesel engine cylinders and heads, steam cylinders and heads, steam boilers, sectional heating boilers, hot water heating boilers, pump housings of all kinds, including mud pumps as used with the rotary pipe drilling rigs for the drilling of deep wells, the repairing of ore and rock crusher housings, locomotive frames, slag pots as used to haul the hot slag from the furnace to the slag dump of smelters, the repairing of engine beds and frames. The repair will impart the same, or if desired greater tensile strength to the repaired part compared with that it originally possessed.

The invention also is applicable to the joining of two separate pieces of metal or any other solid substances that are machinable. In such cases the improved device will impart to the joint the necessary tensile strength without the use of bolts, rivets, rivet-on-patches. On the contrary the entire repair according to the present invention will be made within the crack or break and within the casting or parts to be joined together. After the application of the fastenings, the same may be ground smooth forming a leakproof joint and imparting great tensile strength.

By installing the locking fastenings l2 in their laminations, each fastening is completely cold drawn to the limit, and the highest possible tensile strength is obtained; and due to the surface increase by use of the laminations, a still greater strength is obtained. Thus it isobvious that a joint can be made according to the present invention that will possess greater strength than the iron as the tensile strength of cast iron is much lower than the annealed alloys.

Another important feature of the invention is that the greater the strain on the joint, the greater the sealing quality, as the strain from the right side of the joint will react through the locking fastenings to the left side of the joint and vice versa. This causes a pulling together of the joint when a strain is applied. Therefore, the greater the strain, the greater the sealing quality.

Of course, it will be understood that the locking fastening I! may be composed of three or more intersecting circles or enlarged portions;

portions.

The invention will be effective for the connecting of railroad rails and will eliminate the "click caused by the car wheels as they pass over the gap between the rails. The improved lock will largely replace the present bolt, rivet and weld. The device could be used upon bridges. The joining of the steel spans of a bridge could be punched to receive the locking fastenings. A locking fastening, thick-as the metal, could be hammered into the design, by two men, thus eliminating the heating and throwing of hot rivets. This procedure would sharply step up the assembling of structural steel work of any kind.

It is obvious that various changes and modiiications may be made in the details of construction and design of the above specifically described embodiment of this invention without departing from the spirit thereof, such changes and modifications being restricted only by the scope of the following claims.

What is claimed is:

1. The herein described method for interlocking metallic pieces over a fissure which consists in drilling a plurality of overlapped holes to form an elongated opening across the fissure, introducing into said holes a plurality of locking fastenings shaped to fit into said opening, each of said fastenings having raised portions, and independently punching the raised portions of each of said fastenings down into the same plane with said fastenings, before the introduction of the next fastening into the holes, by the step of cold punching said fastenings whereby to increase the tensile strength of the metallic pieces. 7

2. The herein described method for the uniting of metal pieces across a fissure which consists in producing a counter-sunk design in the metal pieces across said fissure by drilling a central hole through the fissure and subsequently drilling other holes at opposite sides and communicating with said first hole and overlapping said first hole, inserting one upon another in the design thus produced a plurality of locking fastenings having a configuration substantially that of the counter-sunk design and having flanges, and punching each of the fastenings as it is placed in the design and before inserting the succeeding fastening to bring the flange into substantially the same plane with the rest of the fastening whereby to expand the fastening tightly in the counter-sunk design by a cold process.

3. The herein described method for uniting pieces of metal across a fissure which consists in producing a pair of counter-sunk locking designs in the metal pieces across the fissure, and in producing longitudinally of the fissure a third counter-sunk design for sealing the crack, the end portions of the third design being located close to the first two locking designs, and cold punching bulged locking fastenings in said countersunk designs for expanding the same in place.

4. The herein described method of joining metal pieces across a fissure which consists in producing a counter-sunk design having enlarged and constricted parts, across the fissure in said metal pieces, producing a locking fastening of similar design to said counter-sunk design and having a concavo-convex portion, introducing said fastening to said counter-sunk design, and flattening the concavo-convex portion in the counter-sunk design by a cold process.

5. The herein described method of joining metal pieces across a fissure which consists in producing a cavity having enlarged and constricted portions across the fissure in the metal pieces, producing a locking fastening of similar shape to the cavity and having-concavo-convex portions corresponding to the enlarged portions of the cavity, introducing said fastening into said cavity, and flattening the concavo-convex portions of the fastening to spread the fastening into tight contact with the cavity.

HAL W. HARMAN. 

